In New York City, her voice teacher convinced her to audition for a Broadway agent, Gus Sherman, who wanted to put Jones under contract, and with her parents' approval, she resettled in New York City and gave herself one year to become a Broadway performer. She had only $100 in her pocket.[citation needed]

Her first audition was for an open bi-weekly casting call held by John Fearnley, casting director for Rodgers and Hammerstein and their various musicals.[6] At the time, Jones had never heard of Rodgers and Hammerstein.[7] Fearnley was so impressed that he ran across the street to fetch Richard Rodgers, who was rehearsing with an orchestra for an upcoming musical. Rodgers then called Oscar Hammerstein at home.[7] The two saw great potential in Jones. She became the first and only singer to be put under personal contract with the songwriters. They first cast her in a minor role in South Pacific. For her second Broadway show, Me and Juliet, she started as a chorus girl, and then an understudy for the lead role, earning rave reviews in Chicago.[6]

Jones impressed Rodgers and Hammerstein with her musically trained voice and she was cast as the female lead in the film adaptation of their hit musical Oklahoma! in 1955. Other film musicals quickly followed, including Carousel, (1956) April Love (1957) and The Music Man, (1962) in which she was often typecast as a wholesome, kind character. However, she won a 1960 Academy Award for her performance in Elmer Gantry portraying a woman corrupted by the title character played by Burt Lancaster. Her character becomes a prostitute who encounters her seducer years later and takes her revenge. The director, Richard Brooks, had originally fought against her being in the movie, but after seeing her first scene told her she would win an Oscar for her performance.[8] She was reunited with Ron Howard (who had played her brother in The Music Man) in The Courtship of Eddie's Father (1963). Jones landed the role of a lady who fell in love with the professor in Fluffy (1965). She also has an impressive stage résumé, including playing the title character in the Broadway musical Maggie Flynn in 1968.

In 1970, after her film roles dwindled, and after turning down the role of Carol Brady on The Brady Bunch, a role that ultimately went to her best friend, Florence Henderson, Jones was more than happy to be the producers' first choice to audition for the lead role of Shirley Partridge in The Partridge Family, an ABC musical sitcom based loosely on the real-life musical family The Cowsills. The series focused on a young widowed mother whose five children form a pop rock group after the entire family painted its signature bus to travel. She was convinced that the combination of music and comedy would be a surefire hit. Jones realized, however, that:

The problem with Partridge—though it was great for me and gave me an opportunity to stay home and raise my kids—when my agents came to me and presented it to me, they said if you do a series and it becomes a hit show, you will be that character for the rest of your life and your film career will go into the toilet, which is what happened. But I have no regrets.[9]

During its first season, it became a hit and was screened in over 70 countries. Within months, Jones and her co-stars were pop culture television icons. Her real-life twenty-year-old stepson David Cassidy, who was an unknown actor at the time, played Shirley Partridge's eldest son, Keith, and became the hottest teen idol in the country. The show itself also spawned a number of albums and singles by The Partridge Family performed by David Cassidy and Shirley Jones. That same year, "I Think I Love You" reached number one on the Billboard Hot 100 music chart, making Jones the second person, after Frank Sinatra, and the first woman to win an acting Oscar and also have a No. 1 hit on that chart. The Partridge Family won a NARM award for the best selling single of the year in 1970 for their hit "I Think I Love You".[10] In 1971 The Partridge Family were nominated for a Grammy under the Best New Artist category.[11]

Shirley Jones' friendship with David Cassidy's family began in the mid-to-late 1950s, when David was just six, after he learned about his father's divorce from his mother Evelyn Ward. Upon David's first meeting with Shirley before co-starring with her on The Partridge Family, he said, "The day he tells me that they're divorced, he tells me, 'We're remarried, and let me introduce you to my new wife.' He was thrilled when her first film, Oklahoma! (1955), had come out; and my dad took me to see it—I just see her, and I go, uh-oh, it doesn't really quite register with me, 'cause I'm in total shock, because I wanted to hate her, but the instant that I met her, I got the essence of her. She's a very warm open, sweet, good human being. She couldn't have thawed it for me – the coldness and the ice—any more than she did."[12] Shirley was shocked to hear her real-life stepson was going to audition for the role of Keith Partridge. David said, "At the auditions, they introduced me to the lead actress (Shirley Jones) 'cause they had no idea, they had no idea. So I said, 'What are you doing here?' She looked at me and said, 'What are you doing here?' And I said, 'Well, I'm reading for the lead guy.' I said, 'What are you doing here?' She said, 'I'm the mother!'" Cassidy discussed his relationship with his stepmother on the show: "She wasn't my mother, and I can be very open, and we can speak, and we became very close friends. She was a very good role model for me, watching the way, you know, she dealt with people on the set, and watching people revere her."[citation needed] After the show's cancellation, Cassidy remained very close to his half-brothers and the rest of his cast mates, especially Shirley.[citation needed]

Cassidy appeared on many shows alongside his stepmother, including A&E Biography, TV Land Confidential, and The Today Show, and he was one of the presenters of his stepmother's Intimate Portrait on Lifetime Television, and the reality show pilot In Search of the Partridge Family, where he served as co-executive producer. The rest of the cast also celebrated the 25th, 30th, and the 35th anniversaries of The Partridge Family (although Cassidy was unavailable to attend the 25th anniversary in 1995 owing to other commitments). In addition, Jack Cassidy's death in 1976 drew Jones and Cassidy closer as Shirley's three children and stepson mourned their father.[citation needed]

In 1979, Jones tried her hand at television for the second time, starring in Shirley, which, like The Partridge Family, featured a family headed by a widowed mother; but the show failed to win ratings and was canceled toward the middle of the season. Jones also played the "older woman" girlfriend of Drew Carey's character in several episodes of The Drew Carey Show.

Jones in 2010

She also won fans in the memorable dramatic project There Were Times, Dear, in which she played a loyal wife whose husband is dying of Alzheimer's disease; she was nominated for an Emmy Award for this work.[13]

In February 1986, Shirley Jones unveiled her star on the Hollywood Walk of Fame on Vine Street just around the corner from Hollywood Boulevard.

She appeared in a rare revival of Noël Coward's operetta, Bitter Sweet, at the Long Beach Civic Light Opera in 1983. In 2004, Shirley returned to Broadway in a revival of 42nd Street, portraying diva "Dorothy Brock" opposite her son Patrick Cassidy — the first time a mother and son were known to star together on Broadway. In July 2005, Jones revisited the musical Carousel onstage in Massachusetts, portraying "Cousin Nettie".

In 2008, U.K. label Stage Door Records released the retrospective collection Then & Now featuring twenty-four songs from Jones's musical career, including songs from the films Oklahoma!, Carousel and April Love. The album features new recordings of songs including "Beauty and the Beast", "Memory" and a sentimental tribute to The Music Man. She had a recurring role as Burt Chance's mother in the Fox TV comedy series Raising Hope.[13]

On August 5, 1956, Jones married singer and actor Jack Cassidy, with whom she had three sons, Shaun, Patrick, and Ryan. David Cassidy, Jack's only child from his first marriage to actress Evelyn Ward, became her stepson. Divorcing Cassidy in 1974, she later married comic/actor Marty Ingels on November 13, 1977. Despite drastically different personalities and several separations (she filed, then withdrew, a divorce petition in 2002), they remain married. Jones and Ingels wrote an autobiography based on their quirky relationship/marriage, Shirley & Marty: An Unlikely Love Story.[17]

Jones was friends with her late co-star Gordon MacRae and his ex-wife Sheila, and he was named godfather to her first son, Shaun Cassidy. She also admitted that she had a crush on MacRae and was starstruck when she worked opposite him on Oklahoma! and states she is the one who convinced MacRae to take the part as Billy Bigelow in Carousel. Frank Sinatra, who had originally been cast, suddenly dropped out during the first days of filming because each scene had to be shot twice, once in CinemaScope 55 (a wider-than-usual, 55 millimeter, 6-track stereo system) and once in 35mmCinemaScope. Sinatra felt that he should have been paid twice because technically he was shooting two films. Three weeks after he left, they found a way to film the scene once on 55mm, then transfer it onto 35mm.[citation needed]

On the evening of December 11, 1976, after Jones had refused an offer of reconciliation from Jack Cassidy, she received news that her ex-husband's penthouse apartment was on fire. Apparently, the fire started from his lit cigarette when he fell asleep on the couch; the following morning, firefighters found Cassidy's body inside the gutted apartment.[18] Jack "wanted to come back (to me) right up to the day he died", Jones said in a 1983 newspaper interview. "And as I realized later, I wanted him. That's the terrible part. Much as I love Marty and have a wonderful relationship – I'd say this with Marty sitting here – I'm not sure if Jack were alive I'd be married to Marty." Jones was 20 years old when she met Cassidy, who was eight years her senior, and she refers to him as the most influential person in her life.[19]